Acetonyl thioethers



l cycloalkyl, .alkylena "haloalkyl, letoalkyl, and the like. Specicexamples `ofsuch nierca'ptans are' i-propyl mercaptan, nbutylAnfierca'ptan,l i-amyl mercaptan, '.cyclohexyl mercaptain, allyl,mercaptain beta-chloroethyl mer.- captan, thioglycol, and acetonylrner'c'a'ptan.l

The 'reaction mayjbe effected between the monohalogenated acetone andthe freemercap- 1 one'of. the reaction products.

Ierred' to employ water, vor an 'foryexampla ethyl alcohol,

butyl alcohol, benzene', toluene, or xylene.

Patented Nov. 21, 19.44.

, Accrom 'rnIoE'rHnRsi` Glen H. Morey, lflrre Haute, Ind., assignor tovCommercial Solvents Corporation, 11nd .a .corporation of yMzu'ylandTerre Haute,

No Drawing; Application March ys, 1941, Serial No. 382,339

claims (ci. :zest-,593)l 't ff My invex'i-tion relates .to new anduseful organic and more particularly Ito anew sulfur compounds,

class of thioethers.

The'thoethers of my present invention` con-l stitute. the class` ofacetonyl I H j cHrC-fCHr-s-R inwhich R vis an aliphatic radicaL'zthe of.whose atomic weightsr is greater than 29. AThese thloethers havereactive carbonyl groups, andareF active hydrogen atoms adjacent thecarbonyl -groups,..=and are useful for `:the

n y production .of 'derivatives vby yknown ketonevreactions. Theacetonyl thioetherslof this class maybe thioethers repre? sented bythegeneral formula:

"in the reaction, since inthis casethe solvent mixture may vberetluxedto sweep out the gaseous hydrogen halide as it is formed in thereaction. The same `eileetlcould be `secured 'by bubbling an inertA gasthrough the reaction mixture-since-elcrated temperatures are generallyunnecessary for :this reaction. When a'mercaptide rather than afreemercaptan -is -employed in the process, the y reaction `is,desirablyreffected yat vordinary room temperature,` o r at temperaturesup to 40 C.

j When the reaction is apparently concluded, the mixture may Asuitablybe heated to a higher temprepared by the reaction of a monohalogenated ywhich R vis'an aliphatic radical having an equiv;

genated acetone may be employed for Athis purpose, but chloroacetone andbromoaceton'e are nientionedthosein which Rrepresents alkyl,hydroxyalkyl,

y e acetone with a mercaptan of the ytype RSH, in f,

pera-turefor ashort `time tol ensure complete reaction.

` Approximately lecluimolar amounts of monohalogenated .acetone-.and'mercaptan are suitably lemployed in the reaction, although an excess ofleither -of the reactants maybe employed, if desned At they conclusionof the reaction, unreacted. lreactantsv and the ,concurrently-produced Yhalide :may be .separated by standardy methods.

v ymore desirable, particularly the former, Among the mercaptans of theabove class, there mal/be' tan, orfbetweenV the monohalog'enated acetoner.and asalt of the marcaptan, .suchas an alkali I or alkaline .earthmetal saltiV The latter type'fof reaction is preferable, since infthiscase a metal Residual halogen acid and unconsumed react- "an-ts mayusually be separated -by distillation; and metal halides may beseparated uby filtration, if kthereaction was eiected in .an organicsolvent.

Other suitable separation procedures will, of

course, `be apparent-.to those skilled in the art.

' invention may be further illustrated by the Afollowing specificexamples;

E mmpl@ I Approximately 270 parts by weight of n-butyl mercaptan was`slowly added to a reluxing mixture of 395 ,parts by Weight yofchloroacetoneand 445 partsr by Weight of benzene. After the evolution ofhydrogen chloride had ceased, the benzene vdistilled off, .and theresidual product was halide constitutes the concurrent reactionl,prodct, :and substantially .neutral `conditionszmay be V maintainedthroughout. If vthe free mercaptan isemployed in the reaction,a halogen.acid is .the

concurrent reaction product, .and the Yresulting acidity rtends to cause.tar formation, with` 17educed yields of'thioether. It is., of course,obvious A th'atalkaline conditions should also be avoided, sincesuch'conditions favor condensation .or .polymerization reactions ofhalogen atedv ketones, rwhich also tend toireduce the yield of thioetherf intheprocess.

The reaction, is desirably .effected in .an .inert solvent which i-s amutual solvent for `both .o f the reactants, andpreferably is aselective-solventror it is generally pre-y v alcohol or sa hydrocarbonsolvent of relatively low boiling point', as.,

'suitable for this purpose, but

use of a relatively low boiling solvent is particularly desirable if'the free mercaptan is employed i-propyl alcohoL-n- The fractionallydistilled under reduced pressure. Substantially all ofthe product was apure fraction boiling at 116 C. (50 mm). The butyl acetonyl thioetherthus obtained :amounted to 80.8% of the .thoretical yield. This productwas Many solvents are v Darts by weight .of chloroacetone.

a clearl yellow liquid having a .faint suldeflike odor, and aA meltingpoint of 49.5 C.

Analysis: Calculated sulfur content of butyl acetonyl thioether, 21.93%;found, 21.95%. Calculatedvmolecularweight, 141i; found, 148.7.

Example II 1 o Approximately 4.00 parts by weight of sodium hydroxidewas vdissolved in A2.000 parts by weight of water, and approximately-900parts byweight o f .n-butyl mercaptain was added while the mixture wasstirred.rapidly and its temperature maintained at approximately .30 C..To .the

resultingy solution there was .slowly added 925 During this. additionthe mixture was stirred and maintained at a temperature below 30 C.After all of the chloroacetone had been added, the temperature wasraised to '10 C. for about 15 minutes, and the mixture was then cooled,and allowed to separate. The aqueous layer containing the sodiumchloride was discarded, and the oily layer was distilled under reducedpressure. Butyl acetonyl thioether, boiling at 116 C. (50 mm.) wasobtained in a yield of 87.8% yield.

Example III A solution of potassium hydrogen sulfide wasI prepared bysaturating with hydrogen sulfide a weight of potassium hyethyl al-Jl vsolution of 280 parts by droxide in 1600 parts by weight of 95% cohol.To this mixture was added 415 partswby weight of ethylene chlorohydrin,after whichit was boiled for 15 minutes, cooled, and filtered to removethe potassium chloride formed in the re Example IV A solution of sodiumhydrosulde was prepared by dissolving 400 parts by weight of sodiumhydroxide and 1000 parts by weight of water,`and saturating withhydrogen sulde. To this solution `925 parts by weight of chloroacetonewas slowly added while the mixture was stirred rapidly, and itstemperaturer maintained below 30 C. The 'mixture was allowed to stand atthis tem'- perature for a few hours, and was then filtered to remove asolid reaction product of unknown composition, `The ltrate was allowed'to separate, and the oil layer was cooled to crystallize out theacetonyl thioethen'which was then recrystallized from ethyl ether. Theacetonyl thioether constituted a solid of transparent plate-like crystalstructure, melting at 45 C.

Analysis: Calculated sulfur content of acetonyl thioether, 21.93%;found, 22.24%. Calculated molecular yweight of acetonyl thioether,146.1;

slight sulfide odor, to the higher molecular weight products which arecrystalline solids of very slight odor, or no perceptible-odor. Thisclass of compounds is subject to identifying tests for carbonyl andsulfide groups, such as the formation of oximes, phenylhydrazones,sulfoxides, sulof the theoretical.,

found, 153.5. The product was further identified as acetonyl thioetherby the preparation of the 2,4-dinitrophenylhydrazone, which was found tomelt at l85.3 C.

Analysis: Calculated sulfur content of 2,4-dinitrophenylhydrazone of6.32%; found, 6.34%. p l

It may be noted that the above example differs from `the precedingexamples in the method of preparation of the thioether. In this casesodium hydrosuliide, rather than a mercaptan, was used as the initialreactant, and no attempt was made to isolate the acetonyl mercaptan,which undoubtedly constituted, anintermediate in the reaction.

It is to be understood, of course, that the above examples are merelyillustrative, and that my invention is not limited to the particularthioethers of the examples. My invention includes theentire class ofacetonyl thioethers as previously deiined, and as set forth in theappended claims. This class of thioethers comprises relativelynonvolatile compoundsranging from oilyliquids of acetonyl thioether, 4

iones, and the mercurio chloride addition products.

.My invention now having been described, what I claim'v is:

, v1.'In a `process for the preparation of acetonyl ,thioethers of thegeneral formula i CHs-C-CHz-S-R in which R. is an aliphatic radical, thesum of whose atomicweights is greater than 29, the steps which comprisereacting a monohalogenated acetone with a mercaptan of the type I R-S-Hin which R is an aliphatic radical having an equivalent weight greaterthan 29, under substantially neutral conditions and in the presence of amutual solvent for said monohalogenated acetone andr mercaptan, toproduce said acetonyl thioether and the corresponding hydrogen halide,

and removing said hydrogen halide from the reaction mixture as it isformed therein.

2. In a process for the preparation of acetonyl thioethers of thegeneral formula in which R is an aliphatic radical having an equivalentweight greater than 29, under substantially neutral` conditions and inthe presence of` a. mutual solvent for said monohalogenated acetone andmercaptan, to produce said acetonyl thioether and the correspondinghydrogen halide, and removing said hydrogen halide from said mixture asit is formed therein by eiTecting the reaction at the approximate reiluxtemperature of said mixture.

` 3. In a process for the preparation of butyl acetonyl thioether, thesteps which comprise reacting butyl mercaptan with a monohalogcnatedacetone `under substantially neutral conditions and inthe presence of amutual solvent for said butyl mercaptan and monohalogenated acetone, tovproduce saidbutyl acetonyl thioether and the corresponding hydrogenhalide, and removing said hydrogen halide from said mixture as it isformed therein by effecting` the reaction at the approximate refluxtemperature of said mixture.

4. In a,`process for the preparation of betahydroxyethyl acetonylthioether, the steps which comprise reacting thioglycol with amonohalogenated acetone under substantially neutral conditions, and inthe presence of a mutual solvent

